Abstract: The latest study on the south Qinling orogenic belt has yielded some new understandings about the division and correlation of the Mid-and Neo-Proterozoic strara in this region. First, basic dike swarm is widespread in the basement massif of Precambrian. The whole rock Sm-Nd isochron age of the dike swarm is 782±164Ma with εNd=1.5±1.0, and 40Ar-39Ar age of pyroxene and hornblende in it is 750±4Ma and 694.4±21Ma, respectively. It shows a feature of continental tholeiite and is derived from a slightly depleted or underpleted mantle and is a product of breakup of old continent in about 800Ma±. Second, In Wudang area, the relationship of the rift sedimentary volcanic formation of Yaolinghe Group (late Sinian, 800Ma±)and the intermediate-basement rock series of Wudang Group of Middle Proterozoic is of regionally angular unconformity. On the basis of discussion on the division and correlation of Late Precambrian strata in the south Qinling by the theory of plate 1ectonic dynamics, the authors concluded that tile South Qinling Belt has undergone two big events a mountain-building movement during the Jining period and a rifting movement during the Chengjiang period in Neo-Proterozoic, which had controlled the construction and space-time distribution of different rock units. A new division and correlation for the Mid-and Neo Proterozoic strata in the South Qinling is therefore proposed.